molly line live in boss upon -- boston for us now. >> reporter: a new study released by boston university shows they found more than 3,000 leaks, and it raises concerns about everything from air quality to a rare risk of an explosion. there were two explosions across the country earlier this month, one a multistory building that was leveled in springfield, massachusetts, and another deadly blast out in indianapolis reminding all of us of just how powerful natural gas can be. and while the blast here in massachusetts was caused by human error, a pipe that was hit by a drill, the study conducted by boston university raises concerns about the aging infrastructure of one of the nation's oldest cities and just how quickly the old pipes here in boston can be replaced. now, while the majority of leakr nathan phillips and his team found six locations where levels were potentially high enough to cause an explosion. they were, of course, fixed, but the professor says this is a wake-up call to all the parties involved in the gas supply. take a listen. >> these situations, they may be rare, but when